1. Field of the Invention
The present invention relates to a cervical plating system, and more particularly, to a structure that prevents a fastening screw from being dislodged and fixes the position of the fastening screw in a cervical plating system, which fixedly connects two or more vertebrae to each other.
2. Description of Related Art
Operations and manipulation for treating vertebrae having an affliction, such as intervertebral disk disorders, spinal disc herniation, fractured or dislocated vertebrae, or cervical spondylotic myelopathy, generally include a process of fixing vertebrae by connecting them to each other so that they do not move. In order to fixedly connect two or more vertebrae to each other, a vertebral fixing device or cervical plating system has generally been used from the past.
The vertebral fixing device is an implant that is used for vertebrae, and is generally implanted in the front of the vertebrae from the anterior in order to fixedly connect two or more vertebrae to each other when fusing upper and lower vertebrae. Such a vertebral fixing device is generally a vertebral anterior insert that includes a cervical plate and screws. The operator can fixedly fasten the cervical plate to two or more vertebrae by fitting the screws into holes in the cervical plate and then turning the screws using a tool such as a driver.
Here, when the vertebral fixing device is implanted into the human body, it can be fatal to the patient if a screw becomes dislodged from the cervical plate. Thus, a mechanism that can prevent the screws from being dislodged from the cervical plate is required. According to a mechanism that has generally been used in the related art, an auxiliary plate, which covers the heads of the fastening screws, is fastened to the cervical plate using auxiliary screws.
However, since the auxiliary screws, which fasten the auxiliary plate to the cervical plate, gradually become loose such that they can become dislodged from the cervical plate, the mechanism for preventing the screws from being dislodged in the related art has limited stability and reliability.
In addition, in the state in which the vertebral fixing device is implanted in the human body, even if the fastening screw is not completely dislodged from the cervical plate, the fastening between the vertebrae and the screws may become loose by the influence of vibration from the voice of the patient or the like, so that the fastening screw becomes loose and is not securely fixed. This phenomenon acts as a factor that hinders stable fixing of the vertebrae, and in particular, becomes severe if the fastening screws are fastened in a position in which they are inclined at a predetermined fastening angle instead of being vertically fastened to the vertebrae. Therefore, there are demands for a mechanism for stably fixing the position or posture of the fastening screws fastened to the vertebrae.
The information disclosed in this Background of the Invention section is only for the enhancement of understanding of the background of the invention, and should not be taken as an acknowledgment or any form of suggestion that this information forms a prior art that would already be known to a person skilled in the art.